Isolation and analysis of bacteria with antimicrobial activities from the marine sponge Haliclona simulans collected from Irish waters.
Samples of the marine sponge Haliclona simulans were collected from Irish coastal waters, and bacteria were isolated from these samples. Phylogenetic analyses of the cultured isolates showed that four different bacterial phyla were represented; Bacteriodetes, Actinobacteria, Proteobacteria, and Firmicutes. The sponge bacterial isolates were assayed for the production of antimicrobial substances, and biological activities against Gram-positive and Gram-negative bacteria and fungi were demonstrated, with 50% of isolates showing antimicrobial activity against at least one of the test strains. Further testing showed that the antimicrobial activities extended to the important pathogens Pseudomonas aeruginosa, Clostridium difficile, multi-drug-resistant Staphylococcus aureus, and pathogenic yeast strains. The Actinomycetes were numerically the most abundant producers of antimicrobial activities, although activities were also noted from Bacilli and Pseudovibrio isolates. Surveys for the presence of potential antibiotic encoding polyketide synthase and nonribosomal peptide synthetase genes also revealed that genes for the biosynthesis of these secondary metabolites were present in most bacterial phyla but were particularly prevalent among the Actinobacteria and Proteobacteria. This study demonstrates that the culturable fraction of bacteria from the sponge H. simulans is diverse and appears to possess much potential as a source for the discovery of new medically relevant biological active agents.
Kennedy
Jonathan
J
Environmental Research Institute, University College Cork, Cork, Ireland.
Baker
Paul
P
Piper
Clare
C
Cotter
Paul D
PD
Walsh
Marcella
M
Mooij
Marlies J
MJ
Bourke
Marie B
MB
Rea
Mary C
MC
O'Connor
Paula M
PM
Ross
R Paul
RP
Hill
Colin
C
O'Gara
Fergal
F
Marchesi
Julian R
JR
Dobson
Alan D W
AD
D000818:Animals; D000890:Anti-Infective Agents / Q000378:metabolism; D000898:Antibiosis / Q000235:genetics*; D001419:Bacteria / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D016000:Cluster Analysis; D007494:Ireland; D008969:Molecular Sequence Data; D010453:Peptide Synthases / Q000235:genetics; D010802:Phylogeny; D048630:Polyketide Synthases / Q000235:genetics; D011161:Porifera / Q000235:genetics / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S; D017422:Sequence Analysis, DNA; D013045:Species Specificity
D000890:Anti-Infective Agents; D012336:RNA, Ribosomal, 16S; D048630:Polyketide Synthases; D010453:Peptide Synthases